Moved the previously split send_serial_data and receive_serial_data into a single message. Renamed files to use usb_serial instead of usbserial. Updated CMakeLists to actually refer to usb_serial and not motors. Fixed bugs.

This is a broken commit because I decided to do this at a bad time. Sorry! The build will be working after next commit, I promise (and I won't push till then). This commit reflects the licensing in the files after I used my auto-add/remove script.